Purpose Cancer and its treatments often lead to inflammation, muscle problems, and ongoing loss of physical function, as reflected by alterations in circulating microRNAs (miRNAs). In this study, we measured levels of selected muscle- (miR-1, miR-133, miR-208, miR-486, and miR-499) and inflammation-related (miR-21, miR-126, miR-146, and miR-155) miRNAs in breast cancer patients and aimed to explore, using stratified analyses,...